WASHINGTON --- The Nuclear Posture Review released today is a strategy to keep America safe with a deterrent that is modern and credible, Deputy Defense Secretary Patrick M. Shanahan said today in rolling out the strategy.

The NPR reaffirms that the fundamental role of U.S. nuclear policy is deterrence and continues the clear commitment to non-proliferation and arms control, Shanahan said in a Pentagon press briefing.

Shanahan was joined at the event by Deputy Energy Secretary Dan Brouillette and Undersecretary of State for Political Affairs Thomas A. Shannon Jr.

The review took a whole-of-government approach that involved the Departments of Defense, State and Energy, he said. The effort began in January 2017, when President Donald J. Trump directed the review to ensure a safe, secure and effective nuclear deterrent.

The world has changed dramatically since the last review in 2010, Shanahan said.

The NPR takes the evolving threats into consideration in keeping America safe, he said. Both the National Defense Strategy and National Security Strategy call for a safe, secure, effective nuclear deterrent, he pointed out.

Mattis: ‘Current, Pragmatic Assessment’

The review comes at a critical moment in the nation’s history, Defense Secretary James N. Mattis wrote in the preface of the NPR, adding “America confronts an international security situation that is more complex and demanding than any since the end of the Cold War.”

He cited concerns with activities by Russia, China, North Korea and Iran. “We must look reality in the eye and see the world as it is, not as we wish it to be,” Mattis wrote. “This NPR reflects the current, pragmatic assessment of the threats we face and the uncertainties regarding the future security environment.”

There is no “one size fits all” in regards to deterrence, Shanahan said.

While the triad has kept the nation safe for more than 70 years, the United States “cannot afford to let it become obsolete,” the deputy said.

The NPR recommends lowering the yield of some existing submarine-launched ballistic missile warheads, and bringing back a nuclear sea-based launched cruise missile, he said.

Those recommendations, Shanahan noted, do not require developing new nuclear warheads and do not increase the size of the nation’s nuclear stockpile. The recommendations align with nonproliferation commitments and strengthen American deterrence, he said.

According to the review, “expanding flexible U.S. nuclear options now, to include low-yield options, is important for the preservation of credible deterrence against regional aggression.”

Use of Weapons in ‘Extreme Circumstances’

The U.S. does not want to use nuclear weapons, Shanahan said. He noted the NPR says the nation would only consider the use of nuclear weapons in “extreme circumstances to defend the vital interests of the United States, its allies and partners.”

The United States now faces a more diverse and advanced nuclear-threat environment than ever before, “with considerable dynamism in potential adversaries’ development and deployment programs for nuclear weapons and delivery systems,” the NPR states.

The review says it candidly addresses the challenges posed by “Russian, Chinese and other states’ strategic policies, programs and capabilities, particularly nuclear.”

In addition, “flexible, adaptable and resilient U.S. nuclear capabilities [are] now required to protect the United States, [its] allies and partners, and promote strategic stability,” according to the review.

The United States currently operates 14 Ohio-class ballistic missile submarines and will continue to take the steps needed to ensure those submarines remain operationally effective and survivable until replaced by the Columbia-class ballistic missile submarines, the NPR explains.

The United States has initiated the Ground-Based Strategic Deterrent program to begin the replacement of Minuteman III in 2029. The GBSD program will also modernize the 450 ICBM launch facilities that will support the fielding of 400 ICBMs.

The bomber leg of the triad consists of 46 nuclear-capable B-52H Stratofortress and 20 nuclear-capable B-2A Spirit “stealth” strategic bombers. The United States has initiated a program to develop and deploy the next-generation bomber, the B-21 Raider. It will first supplement, and eventually replace elements of the conventional and nuclear-capable bomber force beginning in the mid-2020s.

WASHINGTON --- The United States must recapitalize the nuclear triad and accompanying command-and-control system to continue to maintain deterrence into the future, Defense Secretary James N. Mattis wrote in the preface to the Nuclear Posture Review released today.

In one of his first acts as president, Donald J. Trump directed Mattis to conduct the review, last conducted in 2010.

Nuclear deterrence is based on having credible, effective and flexible systems in place to ensure no enemy miscalculates. The consequences of launching an attack on the U.S. or its allies would be catastrophic to any country launching a first strike.

A credible nuclear deterrent ensures the United States cannot be blackmailed by rogue countries and allows American diplomats to negotiate from strength, Mattis wrote in the foreword to the report.

Changing World

Since 2010, the world situation has changed dramatically. Great power competition has returned. Russia illegally annexed the Crimean Peninsula in 2014. China has sunk substantial resources into their nuclear forces and is pursuing new nuclear capabilities. North Korea has developed nuclear weapons and is working to mate that capability with intercontinental ballistic missiles. Iran’s nuclear program is on hold right now.

Modernizing the force does not lower the nuclear threshold, Mattis said. A credible, modern force ensures that even a limited use of nuclear weapons against the U.S. and its allies would be more costly to an adversary.

“This review comes at a critical moment in our nation’s history, for America confronts an international security situation that is more complex and demanding than any since the end of the Cold War,” Mattis wrote. “In this environment, it is not possible to delay modernization of our nuclear forces if we are to preserve a credible nuclear deterrent.”

The review calls for a flexible, tailored approach that keeps the United States well within treaty limitations. The review says replacement of the nuclear triad and the command and control system must be the priority for the department.

Modernizing the Nuclear Triad

The review finds the nuclear triad -- intercontinental ballistic missiles, submarine-launched ballistic missiles and nuclear-capable aircraft -- remains the best way to ensure deterrence. “The triad provides the president flexibility while guarding against technological surprise or sudden changes in the geopolitical environment,” Mattis said in the foreword. “To remain effective, however, we must recapitalize our Cold War legacy nuclear forces.”

These include replacing the current 400 Minuteman 3 missiles based in silos. The review also calls for replacing 450 ICBM launch facilities to support 400 missiles. Replacement should begin in 2029.

The Navy currently operates 14 Ohio-class ballistic missile submarines. They will be replaced by Columbia-class boomers, the first of which is scheduled to begin construction in 2021.

Finally, the Air Force currently has 46 nuclear-capable bombers split between B-2 stealth bombers and the venerable B-52 Stratofortress. These will be replaced by the B-21 Raider beginning in the mid-2020s.

These capabilities mean nothing if the command, control and communications systems are not also modernized.

“Maintaining an effective nuclear deterrent is much less expensive than fighting a war we were unable to deter,” Mattis wrote. “Maintenance costs for today’s nuclear deterrent are approximately three percent of the annual defense budget. Additional funding of another three or four percent, over more than a decade, will be required to replace these aging systems.”

No president wants to use nuclear weapons, he said, but having these terrible weapons are necessary in today’s uncertain environment. “Nuclear forces, along with our conventional forces and other instruments of national power, are therefore first and foremost directed towards deterring aggression and preserving peace,” the secretary wrote. “Our goal is to convince adversaries they have nothing to gain and everything to lose from the use of nuclear weapons.”